131 research outputs found
Cyberbullying Among Adults: A Qualitative Content Analysis of the Legal Responses to a Complex Social Problem
Cyberbullying is a major issue that is regrettably on the rise. The growth and rapid proliferation of the Internet, social media, and smart mobile devices have widened the audiences, increased anonymity and interactions to further heightened the potential for cyberbullying. While there is a substantial body of literature on cyberbullying there exists two dominant gaps: a lack of studies on adult cyberbullying and novel empirical approaches to understanding cyberbullying. Using information obtained from 75 cyberbullying court cases, this study provides preliminary evidence to better understand cyberbullying amongst adults. Therein, we identify, how cyberbullying occurs in relation to four key entities: the \u27offender,\u27 the \u27technology,\u27 the \u27victim\u27 and the \u27guardianship\u27. We also identify key themes and their relationships that emerged from the court cases that must be further investigated in order to better understand cyberbullying in future work
Educating for Environmental Practices: An Assessment from Bachelor of Commerce (B. Com) Undergraduates in Sri Lankan State Universities
Scholarly attention on environmental literacy has been increased in recent years since the knowledge level and interest in environmental issues are decisive to engage in environmental protection functions. The study aims to investigate the environmental literacy level believing that understanding the level of environmental literacy will lead to influence attitudinal changes and actions of undergraduates towards environment. Total number of 650 Bachelor of Commerce undergraduates in state universities of Sri Lanka were selected as the sample of the study. A self-administered structured questionnaire was administered to collect data on the environmental literacy level, the interest and the activity engagement in environmental activities of the respondents. The regression-based path analysis was performed to examine the relationships among the constructs. Based on the descriptive analysis, there was low level of environmental literacy of the selected undergraduates in this study. The overall level of interest in environmental issues and the level of engagement in environmental activities were moderate. The regression-based path analysis indicated that environmental literacy as well as the environmental interest were significant predictors for environmental engagement. Further, interest in environmental issues mediated the relationship between the environmental literacy and the actual engagement in environmental activities. The study exclusively examined the relationship between the undergraduates' knowledge level of the environment and the interest in environmental issues and also examined the factors that influence undergraduates' participation in activities that promote sustainability of the environment, which has been neglected by prior studies. The results facilitate to recommend that the degree programmes should be integrated with environmental areas where such knowledge could lead to promote the interest and the action towards the environmental activities. Keywords Bachelor of Commerce undergraduates, Comparative study, Environmental literacy, Sustainabilit
Climbing Robot for Steel Bridge Inspection: Design Challenges
Inspection of bridges often requires high risk operations such as working at heights, in confined spaces, in hazardous environments; or sites inaccessible by humans. There is significant motivation for robotic solutions which can carry out these inspection tasks. When inspection robots are deployed in real world inspection scenarios, it is inevitable that unforeseen challenges will be encountered. Since 2011, the New South Wales Roads & Maritime Services and the Centre of Excellence for Autonomous Systems at the University of Technology, Sydney, have been working together to develop an innovative climbing robot to inspect high risk locations on the Sydney Harbour Bridge. Many engineering challenges have been faced throughout the development of several prototype climbing robots, and through field trials in the archways of the Sydney Harbour Bridge. This paper will highlight some of the key challenges faced in designing a climbing robot for inspection, and then present an inchworm inspired robot which addresses many of these challenges
Finding Correspondence between Metabolomic Features in Untargeted Liquid Chromatography-Mass Spectrometry Metabolomics Datasets
Integration of multiple datasets can greatly enhance bioanalytical studies, for example, by increasing power to discover and validate biomarkers. In liquid chromatography-mass spectrometry (LC-MS) metabolomics, it is especially hard to combine untargeted datasets since the majority of metabolomic features are not annotated and thus cannot be matched by chemical identity. Typically, the information available for each feature is retention time (RT), mass-to-charge ratio (m/z), and feature intensity (FI). Pairs of features from the same metabolite in separate datasets can exhibit small but significant differences, making matching very challenging. Current methods to address this issue are too simple or rely on assumptions that cannot be met in all cases. We present a method to find feature correspondence between two similar LC-MS metabolomics experiments or batches using only the features' RT, m/z, and FI. We demonstrate the method on both real and synthetic datasets, using six orthogonal validation strategies to gauge the matching quality. In our main example, 4953 features were uniquely matched, of which 585 (96.8%) of 604 manually annotated features were correct. In a second example, 2324 features could be uniquely matched, with 79 (90.8%) out of 87 annotated features correctly matched. Most of the missed annotated matches are between features that behave very differently from modeled inter-dataset shifts of RT, MZ, and FI. In a third example with simulated data with 4755 features per dataset, 99.6% of the matches were correct. Finally, the results of matching three other dataset pairs using our method are compared with a published alternative method, metabCombiner, showing the advantages of our approach. The method can be applied using M2S (Match 2 Sets), a free, open-source MATLAB toolbox, available at https://github.com/rjdossan/M2S
Finding correspondence between metabolomic features in untargeted liquid chromatography-mass spectrometry metabolomics datasets.
Integration of multiple datasets can greatly enhance bioanalytical studies, for example, by increasing power to discover and validate biomarkers. In liquid chromatography-mass spectrometry (LC-MS) metabolomics, it is especially hard to combine untargeted datasets since the majority of metabolomic features are not annotated and thus cannot be matched by chemical identity. Typically, the information available for each feature is retention time (RT), mass-to-charge ratio (m/z), and feature intensity (FI). Pairs of features from the same metabolite in separate datasets can exhibit small but significant differences, making matching very challenging. Current methods to address this issue are too simple or rely on assumptions that cannot be met in all cases. We present a method to find feature correspondence between two similar LC-MS metabolomics experiments or batches using only the features' RT, m/z, and FI. We demonstrate the method on both real and synthetic datasets, using six orthogonal validation strategies to gauge the matching quality. In our main example, 4953 features were uniquely matched, of which 585 (96.8%) of 604 manually annotated features were correct. In a second example, 2324 features could be uniquely matched, with 79 (90.8%) out of 87 annotated features correctly matched. Most of the missed annotated matches are between features that behave very differently from modeled inter-dataset shifts of RT, MZ, and FI. In a third example with simulated data with 4755 features per dataset, 99.6% of the matches were correct. Finally, the results of matching three other dataset pairs using our method are compared with a published alternative method, metabCombiner, showing the advantages of our approach. The method can be applied using M2S (Match 2 Sets), a free, open-source MATLAB toolbox, available at https://github.com/rjdossan/M2S
Effect of dry or wet substrate deposition on the organic volume fraction of core–shell aerosol particles
Understanding the impact of sea spray aerosol (SSA) on the
climate and atmosphere requires quantitative knowledge of their chemical
composition and mixing states. Furthermore, single-particle measurements are
needed to accurately represent large particle-to-particle variability. To
quantify the mixing state, the organic volume fraction (OVF), defined as the
relative organic volume with respect to the total particle volume, is
measured after generating and collecting aerosol particles, often using
deposition impactors. In this process, the aerosol streams are either dried
or kept wet prior to impacting on solid substrates. However, the atmospheric
community has yet to establish how dry versus wet aerosol deposition
influences the impacted particle morphologies and mixing states. Here, we
apply complementary offline single-particle atomic force microscopy (AFM)
and bulk ensemble high-performance liquid chromatography (HPLC) techniques
to assess the effects of dry and wet deposition modes on the
substrate-deposited aerosol particles' mixing states. Glucose and NaCl
binary mixtures that form core–shell particle morphologies were studied as
model systems, and the mixing states were quantified by measuring the OVF of
individual particles using AFM and compared to the ensemble measured by
HPLC. Dry-deposited single-particle OVF data positively deviated from the
bulk HPLC data by up to 60 %, which was attributed to significant
spreading of the NaCl core upon impaction with the solid substrate. This led
to underestimation of the core volume. This problem was circumvented by (a)Â performing wet deposition and thus bypassing the effects of the solid core
spreading upon impaction and (b) performing a hydration–dehydration cycle on
dry-deposited particles to restructure the deformed NaCl core. Both
approaches produced single-particle OVF values that converge well with the
bulk and expected OVF values, validating the methodology. These findings
illustrate the importance of awareness in how conventional particle
deposition methods may significantly alter the impacted particle
morphologies and their mixing states.</p
Metabolic Deficiences Revealed in the Biotechnologically Important Model Bacterium Escherichia coli BL21(DE3)
The Escherichia coli B strain BL21(DE3) has had a profound impact on biotechnology through its use in the production of recombinant proteins. Little is understood, however, regarding the physiology of this important E. coli strain. We show here that BL21(DE3) totally lacks activity of the four [NiFe]-hydrogenases, the three molybdenum- and selenium-containing formate dehydrogenases and molybdenum-dependent nitrate reductase. Nevertheless, all of the structural genes necessary for the synthesis of the respective anaerobic metalloenzymes are present in the genome. However, the genes encoding the high-affinity molybdate transport system and the molybdenum-responsive transcriptional regulator ModE are absent from the genome. Moreover, BL21(DE3) has a nonsense mutation in the gene encoding the global oxygen-responsive transcriptional regulator FNR. The activities of the two hydrogen-oxidizing hydrogenases, therefore, could be restored to BL21(DE3) by supplementing the growth medium with high concentrations of Ni2+ (Ni2+-transport is FNR-dependent) or by introducing a wild-type copy of the fnr gene. Only combined addition of plasmid-encoded fnr and high concentrations of MoO42− ions could restore hydrogen production to BL21(DE3); however, to only 25–30% of a K-12 wildtype. We could show that limited hydrogen production from the enzyme complex responsible for formate-dependent hydrogen evolution was due solely to reduced activity of the formate dehydrogenase (FDH-H), not the hydrogenase component. The activity of the FNR-dependent formate dehydrogenase, FDH-N, could not be restored, even when the fnr gene and MoO42− were supplied; however, nitrate reductase activity could be recovered by combined addition of MoO42− and the fnr gene. This suggested that a further component specific for biosynthesis or activity of formate dehydrogenases H and N was missing. Re-introduction of the gene encoding ModE could only partially restore the activities of both enzymes. Taken together these results demonstrate that BL21(DE3) has major defects in anaerobic metabolism, metal ion transport and metalloprotein biosynthesis
Systematic Review of Medicine-Related Problems in Adult Patients with Atrial Fibrillation on Direct Oral Anticoagulants
New oral anticoagulant agents continue to emerge on the market and their safety requires assessment to provide evidence of their suitability for clinical use. There-fore, we searched standard databases to summarize the English language literature on medicine-related problems (MRPs) of direct oral anticoagulants DOACs (dabigtran, rivaroxban, apixban, and edoxban) in the treatment of adults with atri-al fibrillation. Electronic databases including Medline, Embase, International Pharmaceutical Abstract (IPA), Scopus, CINAHL, the Web of Science and Cochrane were searched from 2008 through 2016 for original articles. Studies pub-lished in English reporting MRPs of DOACs in adult patients with AF were in-cluded. Seventeen studies were identified using standardized protocols, and two reviewers serially abstracted data from each article. Most articles were inconclusive on major safety end points including major bleeding. Data on major safety end points were combined with efficacy. Most studies inconsistently reported adverse drug reactions and not adverse events or medication error, and no definitions were consistent across studies. Some harmful drug effects were not assessed in studies and may have been overlooked. Little evidence is provided on MRPs of DOACs in patients with AF and, therefore, further studies are needed to establish the safety of DOACs in real-life clinical practice
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